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/*
* ebtable_broute
*
* Authors:
* Bart De Schuymer <bdschuym@pandora.be>
*
* April, 2002
*
* This table lets you choose between routing and bridging for frames
* entering on a bridge enslaved nic. This table is traversed before any
* other ebtables table. See net/bridge/br_input.c.
*/
#include <linux/netfilter_bridge/ebtables.h>
#include <linux/module.h>
#include <linux/if_bridge.h>
/* EBT_ACCEPT means the frame will be bridged
* EBT_DROP means the frame will be routed
*/
static struct ebt_entries initial_chain = {
.name = "BROUTING",
.policy = EBT_ACCEPT,
};
static struct ebt_replace_kernel initial_table =
{
.name = "broute",
.valid_hooks = 1 << NF_BR_BROUTING,
.entries_size = sizeof(struct ebt_entries),
.hook_entry = {
[NF_BR_BROUTING] = &initial_chain,
},
.entries = (char *)&initial_chain,
};
static int check(const struct ebt_table_info *info, unsigned int valid_hooks)
{
if (valid_hooks & ~(1 << NF_BR_BROUTING))
return -EINVAL;
return 0;
}
static const struct ebt_table broute_table =
{
.name = "broute",
.table = &initial_table,
.valid_hooks = 1 << NF_BR_BROUTING,
.check = check,
.me = THIS_MODULE,
};
static int ebt_broute(struct sk_buff *skb)
{
int ret;
ret = ebt_do_table(NF_BR_BROUTING, skb, skb->dev, NULL,
dev_net(skb->dev)->xt.broute_table);
if (ret == NF_DROP)
return 1; /* route it */
return 0; /* bridge it */
}
static int __net_init broute_net_init(struct net *net)
{
net->xt.broute_table = ebt_register_table(net, &broute_table);
if (IS_ERR(net->xt.broute_table))
return PTR_ERR(net->xt.broute_table);
return 0;
}
static void __net_exit broute_net_exit(struct net *net)
{
ebt_unregister_table(net, net->xt.broute_table);
}
static struct pernet_operations broute_net_ops = {
.init = broute_net_init,
.exit = broute_net_exit,
};
static int __init ebtable_broute_init(void)
{
int ret;
ret = register_pernet_subsys(&broute_net_ops);
if (ret < 0)
return ret;
/* see br_input.c */
rcu_assign_pointer(br_should_route_hook, ebt_broute);
return 0;
}
static void __exit ebtable_broute_fini(void)
{
rcu_assign_pointer(br_should_route_hook, NULL);
synchronize_net();
unregister_pernet_subsys(&broute_net_ops);
}
module_init(ebtable_broute_init);
module_exit(ebtable_broute_fini);
MODULE_LICENSE("GPL");
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